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1.
PLoS One ; 19(2): e0292655, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38329960

RESUMO

Thioredoxin-interacting protein (TXNIP) has emerged as a key player in cancer and diabetes since it targets thioredoxin (TRX)-mediated redox regulation and glucose transporter (GLUT)-mediated metabolism. TXNIP consists of two arrestin (ARR, N-ARR and C-ARR) domains at its amino-terminus and two PPxY (PY) motifs and a di-leucine (LL) motif for endocytosis at its carboxyl-terminus. Here, we report that TXNIP shuffles between TRX and GLUTs to regulate homeostasis of intracellular oxidative stress and glucose metabolism. While TXNIP functions as a gatekeeper of TRX by default, it robustly interacted with class I GLUTs through its C-ARR domain upon increase of intracellular reactive oxygen species. This interaction prompted the surface expression downregulation and lysosomal degradation of GLUTs by its carboxyl-terminal LL endocytic signaling motif to attenuate glucose uptake. Consequently, TXNIP expression significantly limited glucose uptake, leading to the suppression of glycolysis, hexosamine biosynthesis, and the pentose phosphate pathway. Our findings establish a fundamental link between ROS and glucose metabolism through TXNIP and provide a promising target for the drug development against GLUT-related metabolic disorders.


Assuntos
Proteínas de Transporte , Diabetes Mellitus , Estresse Oxidativo , Tiorredoxinas , Humanos , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Glucose/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Tiorredoxinas/genética , Tiorredoxinas/metabolismo , Animais , Camundongos
2.
Exp Mol Med ; 55(10): 2116-2126, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37779151

RESUMO

Ubiquitously expressed aminoacyl-tRNA synthetases play essential roles in decoding genetic information required for protein synthesis in every living species. Growing evidence suggests that they also function as crossover mediators of multiple biological processes required for homeostasis. In humans, eight cytoplasmic tRNA synthetases form a central machinery called the multi-tRNA synthetase complex (MSC). The formation of MSCs appears to be essential for life, although the role of MSCs remains unclear. Glutamyl-prolyl-tRNA synthetase 1 (EPRS1) is the most evolutionarily derived component within the MSC that plays a critical role in immunity and metabolism (beyond its catalytic role in translation) via stimulus-dependent phosphorylation events. This review focuses on the role of EPRS1 signaling in inflammation resolution and metabolic modulation. The involvement of EPRS1 in diseases such as cancer is also discussed.


Assuntos
Aminoacil-tRNA Sintetases , Humanos , Aminoacil-tRNA Sintetases/genética , Aminoacil-tRNA Sintetases/metabolismo , Fosforilação , Ligação Proteica , RNA de Transferência/metabolismo
3.
J Integr Plant Biol ; 65(9): 2218-2236, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37195059

RESUMO

Pollen tube growth is essential for successful double fertilization, which is critical for grain yield in crop plants. Rapid alkalinization factors (RALFs) function as ligands for signal transduction during fertilization. However, functional studies on RALF in monocot plants are lacking. Herein, we functionally characterized two pollen-specific RALFs in rice (Oryza sativa) using multiple clustered regularly interspaced palindromic repeats (CRISPR)/CRISPR-associated protein 9-induced loss-of-function mutants, peptide treatment, expression analyses, and tag reporter lines. Among the 41 RALF members in rice, OsRALF17 was specifically expressed at the highest level in pollen and pollen tubes. Exogenously applied OsRALF17 or OsRALF19 peptide inhibited pollen tube germination and elongation at high concentrations but enhanced tube elongation at low concentrations, indicating growth regulation. Double mutants of OsRALF17 and OsRALF19 (ralf17/19) exhibited almost full male sterility with defects in pollen hydration, germination, and tube elongation, which was partially recovered by exogenous treatment with OsRALF17 peptide. This study revealed that two partially functionally redundant OsRALF17 and OsRALF19 bind to Oryza sativa male-gene transfer defective 2 (OsMTD2) and transmit reactive oxygen species signals for pollen tube germination and integrity maintenance in rice. Transcriptomic analysis confirmed their common downstream genes, in osmtd2 and ralf17/19. This study provides new insights into the role of RALF, expanding our knowledge of the biological role of RALF in regulating rice fertilization.


Assuntos
Oryza , Tubo Polínico , Tubo Polínico/genética , Pólen/genética , Transdução de Sinais , Peptídeos
4.
Nat Commun ; 13(1): 6455, 2022 10 29.
Artigo em Inglês | MEDLINE | ID: mdl-36309524

RESUMO

The AKT signaling pathway plays critical roles in the resolution of inflammation. However, the underlying mechanisms of anti-inflammatory regulation and signal coordination remain unclear. Here, we report that anti-inflammatory AKT signaling is coordinated by glutamyl-prolyl-tRNA synthetase 1 (EPRS1). Upon inflammatory activation, AKT specifically phosphorylates Ser999 of EPRS1 in the cytoplasmic multi-tRNA synthetase complex, inducing release of EPRS1. EPRS1 compartmentalizes AKT to early endosomes via selective binding to the endosomal membrane lipid phosphatidylinositol 3-phosphate and assembles an AKT signaling complex specific for anti-inflammatory activity. These events promote AKT activation-mediated GSK3ß phosphorylation, which increase anti-inflammatory cytokine production. EPRS1-deficient macrophages do not assemble the early endosomal complex and consequently exacerbate inflammation, decreasing the survival of EPRS1-deficient mice undergoing septic shock and ulcerative colitis. Collectively, our findings show that the housekeeping protein EPRS1 acts as a mediator of inflammatory homeostasis by coordinating compartment-specific AKT signaling.


Assuntos
Proteínas Proto-Oncogênicas c-akt , Transdução de Sinais , Camundongos , Animais , Proteínas Proto-Oncogênicas c-akt/metabolismo , Anti-Inflamatórios/farmacologia , Inflamação
5.
J Biol Chem ; 296: 100777, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33992647

RESUMO

Opportunistic bacteria strategically dampen their virulence to allow them to survive and propagate in hosts. However, the molecular mechanisms underlying virulence control are not clearly understood. Here, we found that the opportunistic pathogen Vibrio vulnificus biotype 3, which caused an outbreak of severe wound and intestinal infections associated with farmed tilapia, secretes significantly less virulent multifunctional autoprocessing repeats-in-toxin (MARTX) toxin, which is the most critical virulence factor in other clinical Vibrio strains. The biotype 3 MARTX toxin contains a cysteine protease domain (CPD) evolutionarily retaining a unique autocleavage site and a distinct ß-flap region. CPD autoproteolytic activity is attenuated following its autocleavage because of the ß-flap region. This ß-flap blocks the active site, disabling further autoproteolytic processing and release of the modularly structured effector domains within the toxin. Expression of this altered CPD consequently results in attenuated release of effectors by the toxin and significantly reduces the virulence of V. vulnificus biotype 3 in cells and in mice. Bioinformatic analysis revealed that this virulence mechanism is shared in all biotype 3 strains. Thus, these data provide new insights into the mechanisms by which opportunistic bacteria persist in an environmental reservoir, prolonging the potential to cause outbreaks.


Assuntos
Proteínas de Bactérias/metabolismo , Toxinas Bacterianas/metabolismo , Vibrioses/metabolismo , Vibrio vulnificus/patogenicidade , Fatores de Virulência/metabolismo , Animais , Proteínas de Bactérias/química , Toxinas Bacterianas/química , Células HeLa , Interações Hospedeiro-Patógeno , Humanos , Camundongos , Modelos Moleculares , Vibrio vulnificus/fisiologia , Fatores de Virulência/química
6.
BMC Pharmacol Toxicol ; 22(1): 7, 2021 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-33472699

RESUMO

BACKGROUND: Oxidative damage to retinal pigment epithelial (RPE) cells contributes to the development of age-related macular degeneration, which is among the leading causes of visual loss in elderly people. In the present study, we evaluated the protective role of triphenylphosphonium (TPP)-Niacin against hydrogen peroxide (H2O2)-induced oxidative stress in RPE cells. METHODS: The cellular viability, lactate dehydrogenase release, reactive oxygen species (ROS) generation, and mitochondrial function of retinal ARPE-19 cells were determined under treatment with H2O2 or pre-treatment with TPP-Niacin. The expression level of mitochondrial related genes and some transcription factors were assessed using real-time polymerase chain reaction (RT-qPCR). RESULTS: TPP-Niacin significantly improved cell viability, reduced ROS generation, and increased the antioxidant enzymes in H2O2-treated ARPE-19 cells. Mitochondrial dysfunction from the H2O2-induced oxidative stress was also considerably diminished by TPP-Niacin treatment, along with reduction of the mitochondrial membrane potential (MMP) and upregulation of the mitochondrial-associated gene. In addition, TPP-Niacin markedly enhanced the expression of transcription factors (PGC-1α and NRF2) and antioxidant-associated genes (especially HO-1 and NQO-1). CONCLUSION: We verified the protective effect of TPP-Niacin against H2O2-induced oxidative stress in RPE cells. TPP-Niacin is believed to protect against mitochondrial dysfunction by upregulating antioxidant-related genes, such as PGC-1α, NRF2, HO-1, and NQO-1, in RPE cells.


Assuntos
Antioxidantes/farmacologia , Mitocôndrias/efeitos dos fármacos , Niacina/análogos & derivados , Niacina/farmacologia , Compostos Organofosforados/farmacologia , Epitélio Pigmentado da Retina/citologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Células Epiteliais/fisiologia , Expressão Gênica/efeitos dos fármacos , Humanos , Peróxido de Hidrogênio , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/fisiologia , Estresse Oxidativo/efeitos dos fármacos , Oxirredutases/metabolismo
7.
Biomedicines ; 8(11)2020 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-33142744

RESUMO

Although family with sequence similarity 188 member B (FAM188B) is known to be a member of a novel putative deubiquitinase family, its biological role has not been fully elucidated. Here, we demonstrate the oncogenic function of FAM188B via regulation of forkhead box M1 (FOXM1), another oncogenic transcription factor, in lung cancer cells. FAM188B knockdown induced the inhibition of cell growth along with the downregulation of mRNA and protein levels of FOXM1. FAM188B knockdown also resulted in downregulation of Survivin and cell cycle-related proteins, which are direct targets of FOXM1. Interestingly, FOXM1 co-immunoprecipitated with FAM188B, and the levels of FOXM1 ubiquitination increased with FAM188B knockdown but decreased with FAM188B overexpression. In addition, in vivo xenograft of FAM188B siRNA (siFAM188B) RNA-treated cells resulted in the retardation of tumor growth compared with that in the control. Furthermore, protein levels of FAM188B and FOXM1 were elevated in the human lung cancer tissues, and FAM188B expression was negatively correlated with the overall survival of lung cancer patients. These results indicate that FAM188B exerts its oncogenic effects by regulating FOXM1 deubiquitination and thus its stability. Therefore, FAM188B might be a potential therapeutic target to control lung cancer progression.

8.
mSphere ; 5(4)2020 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-32817457

RESUMO

To understand toxin-stimulated host-pathogen interactions, we performed dual-transcriptome sequencing experiments using human epithelial (HT-29) and differentiated THP-1 (dTHP-1) immune cells infected with the sepsis-causing pathogen Vibrio vulnificus (either the wild-type [WT] pathogen or a multifunctional-autoprocessing repeats-in-toxin [MARTX] toxin-deficient strain). Gene set enrichment analyses revealed MARTX toxin-dependent responses, including negative regulation of extracellular related kinase 1 (ERK1) and ERK2 (ERK1/2) signaling and cell cycle regulation in HT-29 and dTHP-1 cells, respectively. Further analysis of the expression of immune-related genes suggested that the MARTX toxin dampens immune responses in gut epithelial cells but accelerates inflammation and nuclear factor κB (NF-κB) signaling in immune cells. With respect to the pathogen, siderophore biosynthesis genes were significantly more highly expressed in WT V. vulnificus than in the MARTX toxin-deficient mutant upon infection of dTHP-1 cells. Consistent with these results, iron homeostasis genes that limit iron levels for invading pathogens were overexpressed in WT V. vulnificus-infected dTHP-1 cells. Taken together, these results suggest that MARTX toxin regulates host inflammatory responses during V. vulnificus infection while also countering host defense mechanisms such as iron limitation.IMPORTANCEV. vulnificus is an opportunistic human pathogen that can cause life-threatening sepsis in immunocompromised patients via seafood poisoning or wound infection. Among the toxic substances produced by this pathogen, the MARTX toxin greatly contributes to disease progression by promoting the dysfunction and death of host cells, which allows the bacteria to disseminate and colonize the host. In response to this, host cells mount a counterattack against the invaders by upregulating various defense genes. In this study, the gene expression profiles of both host cells and V. vulnificus were analyzed by RNA sequencing to gain a comprehensive understanding of host-pathogen interactions. Our results suggest that V. vulnificus uses the MARTX toxin to subvert host cell immune responses as well as to oppose host counterattacks such as iron limitation.


Assuntos
Toxinas Bacterianas/metabolismo , Células Epiteliais/microbiologia , Interações Hospedeiro-Patógeno/genética , Vibrio vulnificus/genética , Toxinas Bacterianas/genética , Perfilação da Expressão Gênica , Células HT29 , Interações Hospedeiro-Patógeno/imunologia , Humanos , Ferro/metabolismo , Proteína Quinase 1 Ativada por Mitógeno/genética , Proteína Quinase 3 Ativada por Mitógeno/genética , Sideróforos/genética , Células THP-1 , Vibrio vulnificus/patogenicidade , Fatores de Virulência/genética
9.
Medicine (Baltimore) ; 99(29): e20799, 2020 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-32702823

RESUMO

Sessile serrated adenomas (SSAs) are precursors of colorectal cancer (CRC). However, there are limited data on detection rates of this premalignant lesion during colonoscopy surveillance in patients with a history of left side colonic resection for cancer. We aimed to identify the incidence and risk factors of SSAs in post-left side colectomy patients.We retrospectively reviewed the medical records of patients who had undergone left side colectomy for colon and rectal cancer between September 2009 and September 2016 and had at least 1 follow-up colonoscopy. Patient baseline characteristics, SSA diagnoses and characteristics, and colonoscopy information were collected.In total, 539 patients were enrolled. At the first follow-up (mean duration 11.5 months), 98 SSAs were identified (22.2%). At the second follow-up (mean duration 25.8 months), 51 SSAs were identified in 212 patients (24.0%). Multivariate analysis showed that alcohol intake (hazard ratio [HR] 1.524; 95% confidence interval [CI] .963-2.411, P = .041), excellent bowel preparation (HR 2.081; 95% CI 1.214-3.567, P = .049), and use of a transparent cap (HR 1.702; 95% CI 1.060-2.735, P = .013) were associated with higher SSA incidence in the first surveillance colonoscopy, while body mass index (BMI) ≥ 25.0 (HR 1.602; 95% CI 1.060-2.836) was associated with a significantly increased risk of SSAs in the second surveillance.Considering the endoscopic appearance of SSAs, adequate bowel preparation and use of transparent caps during postoperative surveillance colonoscopy can increase the diagnosis rate. Modification of alcohol intake and BMI may reduce the incidence of SSAs in left side colon cancer patients.


Assuntos
Adenoma/epidemiologia , Adenoma/patologia , Neoplasias Colorretais/cirurgia , Idoso , Consumo de Bebidas Alcoólicas/efeitos adversos , Índice de Massa Corporal , Catárticos/efeitos adversos , Colectomia/efeitos adversos , Colonoscopia/métodos , Neoplasias Colorretais/complicações , Neoplasias Colorretais/patologia , Feminino , Seguimentos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias/métodos , Cuidados Pós-Operatórios/métodos , Estudos Retrospectivos , Fatores de Risco
10.
J Immunother Cancer ; 8(1)2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32461342

RESUMO

BACKGROUND: The generation of antigen-specific cytotoxic T lymphocyte (CTL) responses is required for successful cancer vaccine therapy. In this regard, ligands of Toll-like receptors (TLRs) have been suggested to activate adaptive immune responses by modulating the function of antigen-presenting cells (APCs). Despite their therapeutic potential, the development of TLR ligands for immunotherapy is often hampered due to rapid systemic toxicity. Regarding the safety concerns of currently available TLR ligands, finding a new TLR agonist with potent efficacy and safety is needed. METHODS: A unique structural domain (UNE-C1) was identified as a novel TLR2/6 in the catalytic region of human cysteinyl-tRNA synthetase 1 (CARS1) using comprehensive approaches, including RNA sequencing, the human embryonic kidney (HEK)-TLR Blue system, pull-down, and ELISA. The potency of its immunoadjuvant properties was analyzed by assessing antigen-specific antibody and CTL responses. In addition, the efficacy of tumor growth inhibition and the presence of the tumor-infiltrating leukocytes were evaluated using E.G7-OVA and TC-1 mouse models. The combined effect of UNE-C1 with an immune checkpoint inhibitor, anti-CTLA-4 antibody, was also evaluated in vivo. The safety of UNE-C1 immunization was determined by monitoring splenomegaly and cytokine production in the blood. RESULTS: Here, we report that CARS1 can be secreted from cancer cells to activate immune responses via specific interactions with TLR2/6 of APCs. A unique domain (UNE-C1) inserted into the catalytic region of CARS1 was determined to activate dendritic cells, leading to the stimulation of robust humoral and cellular immune responses in vivo. UNE-C1 also showed synergistic efficacy with cancer antigens and checkpoint inhibitors against different cancer models in vivo. Further, the safety assessment of UNE-C1 showed lower systemic cytokine levels than other known TLR agonists. CONCLUSIONS: We identified the endogenous TLR2/6 activating domain from human cysteinyl-tRNA synthetase CARS1. This novel TLR2/6 ligand showed potent immune-stimulating activity with little toxicity. Thus, the UNE-C1 domain can be developed as an effective immunoadjuvant with checkpoint inhibitors or cancer antigens to boost antitumor immunity.


Assuntos
Aminoacil-tRNA Sintetases/metabolismo , Vacinas Anticâncer/administração & dosagem , Imunidade Celular/imunologia , Imunoterapia/métodos , Neoplasias Experimentais/terapia , Receptor 2 Toll-Like/imunologia , Aminoacil-tRNA Sintetases/química , Aminoacil-tRNA Sintetases/imunologia , Animais , Vacinas Anticâncer/imunologia , Domínio Catalítico , Células Dendríticas/imunologia , Feminino , Humanos , Imunização , Ligantes , Camundongos , Camundongos Endogâmicos C57BL , Neoplasias Experimentais/imunologia , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Linfócitos T Citotóxicos/imunologia , Receptor 2 Toll-Like/química , Receptor 2 Toll-Like/metabolismo
11.
PLoS One ; 15(1): e0227694, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31961894

RESUMO

OBJECTIVES: Diabetes is a global epidemic, and the high cost of annually and quantitatively measuring urine albumin excretion using the turbidimetric immunoassay is challenging. We aimed to determine whether a semi-quantitative urinary albumin-creatinine ratio test could be used as a screening tool for microalbuminuria in diabetic patients. METHODS: We assessed the diagnostic accuracy of the semi-quantitative method. The costs of false results in the semi-quantitative method were calculated based on the annual probability of disease progression analyzed through a systematic literature review and meta-analysis. The pooled long-term cost-saving effect of the semi-quantitative method compared with the quantitative test was assessed using a Markov model simulating a long-term clinical setting. Diagnostic accuracy and the cost-saving effect were also validated in an independent external cohort. RESULTS: Compared with the quantitative test, the semi-quantitative method had sensitivities of 93.5% and 81.3% and specificities of 61.4% and 63.1% in the overall sample of diabetic patients (n = 1,881) and in diabetic patients with eGFR ≥60 ml/min/1.73 m2 and a negative dipstick test (n = 1,110), respectively. After adjusting for direct and indirect medical costs, including the risk of disease progression, which was adjusted by the meta-analyzed hazard ratio for clinical outcomes, it was determined that using the semi-quantitative method could save 439.4 USD per person for 10 years. Even after adjusting the result to the external validation cohort, 339.6 USD could be saved for one diabetic patient for 10 years. CONCLUSIONS: The semi-quantitative method could be an appropriate screening tool for albuminuria in diabetic patients. Moreover, it can minimize the testing time and inconvenience and significantly reduce national health costs.


Assuntos
Albuminúria/diagnóstico , Diabetes Mellitus/urina , Nefropatias Diabéticas/diagnóstico , Nefropatias Diabéticas/urina , Programas de Rastreamento/métodos , Urinálise/métodos , Albuminúria/urina , Estudos de Coortes , Redução de Custos/estatística & dados numéricos , Humanos , Programas de Rastreamento/economia , Reprodutibilidade dos Testes , República da Coreia , Urinálise/economia , Urinálise/estatística & dados numéricos
12.
Medicine (Baltimore) ; 99(4): e18928, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31977908

RESUMO

Computed tomography (CT) is widely used in the pretreatment period of early gastric cancer (EGC). Only few studies have reported low accuracy of CT imaging for T and N staging in patients with EGC. However, owing to the limited number of studies, the value of CT imaging for EGC staging is not well known. Thus, we conducted a retrospective cross-sectional study regarding the associations among submucosal invasion, lymph node metastasis, and CT findings.The medical records of patients with EGC who had surgery or endoscopic resection were reviewed in a single center from January 2011 to December 2016. We evaluated the histological type, invasion depth, and lymph node (LN) metastasis on the basis of two-dimensional CT findings.We enrolled 1544 patients. Submucosal (SM) invasion was related to tumor size, histological type, and wall thickening or enhancement on CT images. Deep SM invasion (>500 µm) was also related to tumor size, poorly differentiated type, and abnormal CT findings (wall thickening, enhancement, and central depression). Among the patients with LN reactive positivity (0.5-1 cm), those who were female and had a tumor invasion of >1000 µm showed a higher prevalence of LN metastasis. The false-negative LN group had a higher prevalence of large tumors (>3 cm), poor differentiation, and SM invasion than the true-negative group.Wall thickening, enhancement, and central depression on CT images might be related to SM invasion. Patients with any positive CT findings needs more attention when performing ESD.


Assuntos
Tomada de Decisões , Metástase Linfática/diagnóstico por imagem , Invasividade Neoplásica/diagnóstico por imagem , Neoplasias Gástricas/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Idoso , Estudos Transversais , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias/métodos , Período Pré-Operatório , Estudos Retrospectivos , Neoplasias Gástricas/patologia , Neoplasias Gástricas/cirurgia
13.
Life Sci Space Res (Amst) ; 27: 64-73, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34756232

RESUMO

We report on the contributions of model factors that appear in projection models to the overall uncertainty in cancer risks predictions for exposures to galactic cosmic ray (GCR) in deep space, including comparisons with revised low LET risks coefficients. Annual GCR exposures to astronauts at solar minimum are considered. Uncertainties in low LET risk coefficients, dose and dose-rate modifiers, quality factors (QFs), space radiation organ doses, non-targeted effects (NTE) and increased tumor lethality at high LET compared to low LET radiation are considered. For the low LET reference radiation parameters we use a revised assessment of excess relative risk (ERR) and excess additive risk (EAR) for radiation induced cancers in the Life-Span Study (LSS) of the Atomic bomb survivors that was recently reported, and also consider ERR estimates for males from the International Study of Nuclear Workers (INWORKS). For 45-y old females at mission age the risk of exposure induced death (REID) per year and 95% confidence intervals is predicted as 1.6% [0.71, 1.63] without QF uncertainties and 1.64% [0.69, 4.06] with QF uncertainties. However, fatal risk predictions increase to 5.83% [2.56, 9.7] based on a sensitivity study of the inclusion of non-targeted effects on risk predictions. For males a comparison using LSS or INWORKS lead to predictions of 1.24% [0.58, 3.14] and 2.45% [1.23, 5.9], respectively without NTEs. The major conclusion of our report is that high LET risk prediction uncertainties due to QFs parameters, NTEs, and possible increase lethality at high LET are dominant contributions to GCR uncertainties and should be the focus of space radiation research.


Assuntos
Radiação Cósmica , Neoplasias Induzidas por Radiação , Voo Espacial , Benchmarking , Radiação Cósmica/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Induzidas por Radiação/epidemiologia , Neoplasias Induzidas por Radiação/etiologia , Risco , Medição de Risco , Incerteza
14.
Nat Chem Biol ; 16(1): 31-41, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31792442

RESUMO

A tumorigenic factor, AIMP2 lacking exon 2 (AIMP2-DX2), is often upregulated in many cancers. However, how its cellular level is determined is not understood. Here, we report heat-shock protein HSP70 as a critical determinant for the level of AIMP2-DX2. Interaction of the two factors was identified by interactome analysis and structurally determined by X-ray crystallography and NMR analyses. HSP70 recognizes the amino (N)-terminal flexible region, as well as the glutathione S-transferase domain of AIMP2-DX2, via its substrate-binding domain, thus blocking the Siah1-dependent ubiquitination of AIMP2-DX2. AIMP2-DX2-induced cell transformation and cancer progression in vivo was further augmented by HSP70. A positive correlation between HSP70 and AIMP2-DX2 levels was shown in various lung cancer cell lines and patient tissues. Chemical intervention in the AIMP2-DX2-HSP70 interaction suppressed cancer cell growth in vitro and in vivo. Thus, this work demonstrates the importance of the interaction between AIMP2-DX2 and HSP70 on tumor progression and its therapeutic potential against cancer.


Assuntos
Proteínas de Choque Térmico HSP70/metabolismo , Neoplasias Pulmonares/metabolismo , Proteínas Nucleares/metabolismo , Processamento Alternativo , Animais , Linhagem Celular Tumoral , Transformação Celular Neoplásica , Cristalografia por Raios X , Progressão da Doença , Feminino , Regulação Neoplásica da Expressão Gênica , Células HEK293 , Humanos , Espectroscopia de Ressonância Magnética , Camundongos , Camundongos Endogâmicos BALB C , Ligação Proteica , Mapeamento de Interação de Proteínas , Multimerização Proteica , Ressonância de Plasmônio de Superfície , Ubiquitina/química
15.
Biomater Sci ; 8(4): 1101-1105, 2020 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-31793928

RESUMO

For mRNA mediated cancer immunotherapy, Pam3 was incorporated as an adjuvant within lipid nanoparticles (LNPs) with OVA mRNA. The developed Pam3 incorporated LNPs showed successful expression of tumor antigens with enhanced immune stimulation. We demonstrated that the synergies of Pam3 LNPs could greatly improve the efficacy of tumor prevention by mRNA vaccines.


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Lipopeptídeos/administração & dosagem , Neoplasias/tratamento farmacológico , Ovalbumina/genética , RNA Mensageiro/administração & dosagem , Adjuvantes Imunológicos/química , Animais , Vacinas Anticâncer/administração & dosagem , Vacinas Anticâncer/uso terapêutico , Linhagem Celular , Humanos , Imunoterapia , Injeções Intramusculares , Lipídeos/química , Lipopeptídeos/química , Lipopeptídeos/uso terapêutico , Camundongos , Nanopartículas , Neoplasias/imunologia , Tamanho da Partícula , RNA Mensageiro/química , Ensaios Antitumorais Modelo de Xenoenxerto
16.
Exp Mol Med ; 51(10): 1-14, 2019 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-31666502

RESUMO

Dysregulated immune responses and impaired function in intestinal epithelial cells contribute to the pathogenesis of inflammatory bowel disease (IBD). Growth arrest and DNA damage-inducible 45 beta (Gadd45ß) has been implicated in the pathogenesis of various inflammatory symptoms. However, the role of Gadd45ß in IBD is completely unknown. This study aimed to evaluate the role of Gadd45ß in IBD. Gadd45ß-KO mice exhibited drastically greater susceptibility to dextran sulfate sodium (DSS)-induced colitis and mortality than C57BL/6J mice. Bone marrow transplantation experiments revealed that Gadd45ß functions predominantly in the intestinal epithelium and is critical during the recovery phase. Gadd45ß regulates the TGF-ß signaling pathway in colon tissue and epithelial cells by inhibiting Smurf-mediated degradation of TGF-ß receptor type 1 via competitive binding to the N-terminal domain of Smad7. Furthermore, these results indicate that the Gadd45ß-regulated TGF-ß signaling pathway is involved in wound healing by enhancing epithelial restitution. These results expand the current understanding of the function of Gadd45ß and its therapeutic potential in ulcerative colitis.


Assuntos
Proteínas de Ciclo Celular/genética , Colite Ulcerativa/genética , Colite/genética , Doenças Inflamatórias Intestinais/genética , Fator de Crescimento Transformador beta1/genética , Animais , Colite/induzido quimicamente , Colite/patologia , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/patologia , Colo/patologia , Sulfato de Dextrana/toxicidade , Modelos Animais de Doenças , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Humanos , Doenças Inflamatórias Intestinais/induzido quimicamente , Doenças Inflamatórias Intestinais/patologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Camundongos , Proteólise , Transdução de Sinais/genética , Proteína Smad7/genética , Ubiquitina-Proteína Ligases/genética , Cicatrização/genética
17.
Proc Natl Acad Sci U S A ; 116(36): 18031-18040, 2019 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-31427506

RESUMO

Upon invading target cells, multifunctional autoprocessing repeats-in-toxin (MARTX) toxins secreted by bacterial pathogens release their disease-related modularly structured effector domains. However, it is unclear how a diverse repertoire of effector domains within these toxins are processed and activated. Here, we report that Makes caterpillars floppy-like effector (MCF)-containing MARTX toxins require ubiquitous ADP-ribosylation factor (ARF) proteins for processing and activation of intermediate effector modules, which localize in different subcellular compartments following limited processing of holo effector modules by the internal cysteine protease. Effector domains structured tandemly with MCF in intermediate modules become disengaged and fully activated by MCF, which aggressively interacts with ARF proteins present at the same location as intermediate modules and is converted allosterically into a catalytically competent protease. MCF-mediated effector processing leads ultimately to severe virulence in mice via an MCF-mediated ARF switching mechanism across subcellular compartments. This work provides insight into how bacteria take advantage of host systems to induce systemic pathogenicity.


Assuntos
Fatores de Ribosilação do ADP , ADP-Ribosilação , Toxinas Bacterianas , Vibrio vulnificus , Fatores de Ribosilação do ADP/química , Fatores de Ribosilação do ADP/metabolismo , Animais , Toxinas Bacterianas/química , Toxinas Bacterianas/metabolismo , Células HEK293 , Células HeLa , Humanos , Camundongos , Domínios Proteicos , Vibrio vulnificus/genética , Vibrio vulnificus/metabolismo , Vibrio vulnificus/patogenicidade
18.
PLoS One ; 14(7): e0220196, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31329652

RESUMO

Middle East respiratory syndrome coronavirus (MERS-CoV) causes an acute and severe lower respiratory illness as well as vomiting, diarrhea, and renal failure. Because no licensed MERS-CoV vaccines are currently available, preventive and therapeutic measures are urgently needed. The surface spike (S) glycoprotein of MERS-CoV, which binds to the cellular receptor dipeptidyl peptidase 4 (DPP4), is considered as a major target for MERS-CoV vaccine development. Here, we designed recombinant replication-deficient adenovirus-based vaccines expressing the N-terminal domain (rAd/NTD) and receptor-binding domain (rAd/RBD) of the MERS-CoV S1 subunit and full-length Spike protein (rAd/Spike). We found that immunization with candidate vaccines via intranasal route induced S1-specific IgG antibodies and neutralizing antibodies against MERS spike pseudotyped virus. Especially, rAd/Spike induced the highest neutralizing antibody titer and the strongest cytokine-induced T cell responses among the three candidate vaccines. To compare the immune responses induced by different administration routes, rAd/Spike was administered via intranasal, sublingual, or intramuscular route. All these administration routes exhibited neutralizing effects in the serum. MERS-CoV-specific neutralizing IgA antibodies in the bronchoalveolar lavage fluid were only induced by intranasal and sublingual administration but not by intramuscular administration. Intranasal administration with rAd/Spike also created resident memory CD8 T cells in the airway and lung parenchyma. Taken together, our results showed that both the humoral and cellular immune responses are highly induced by rAd/Spike administration, suggesting that rAd/Spike may confer protection against MERS-CoV infection.


Assuntos
Infecções por Coronavirus/imunologia , Coronavírus da Síndrome Respiratória do Oriente Médio/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Vacinação/métodos , Adenoviridae/genética , Adenoviridae/imunologia , Administração Intranasal , Animais , Anticorpos Neutralizantes/imunologia , Células Cultivadas , Infecções por Coronavirus/prevenção & controle , Feminino , Células HEK293 , Humanos , Imunoglobulina A/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Glicoproteína da Espícula de Coronavírus/genética , Spodoptera , Vacinas Sintéticas/genética , Vacinas Sintéticas/imunologia
19.
Antiviral Res ; 163: 19-28, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30639307

RESUMO

Nucleoprotein is highly conserved among each type of influenza viruses (A and B) and has received significant attention as a good target for universal influenza vaccine. In this study, we determined whether a recombinant adenovirus encoding nucleoprotein of type B influenza virus (rAd/B-NP) confers protection against influenza virus infection in mice. We also identified a cytotoxic T lymphocyte epitope in the nucleoprotein to determine B-NP-specific CD8 T-cell responses. We found that B-NP-specific CD8 T cells induced by rAd/B-NP immunization played a major role in protection following influenza B virus infection using CD8 knockout mice. To assess the effects of the administration routes on protective immunity, we immunized mice with rAd/B-NP via intranasal or intramuscular routes. Both groups showed strong NP-specific humoral and CD8 T-cell responses, but only intranasal immunization provided complete protection against both lineages of influenza B virus challenge. Intranasal but not intramuscular administration established resident memory CD8 T cells in the airway and lung parenchyma, which were required for efficient protection. Furthermore, rAd/B-NP in combination with rAd/A-NP protected mice against lethal infection with both influenza A and B viruses. These findings demonstrate that rAd/B-NP could be further developed as a universal vaccine against influenza.


Assuntos
Imunidade nas Mucosas , Vírus da Influenza B/imunologia , Vacinas contra Influenza/imunologia , Influenza Humana/prevenção & controle , Nucleoproteínas/imunologia , Infecções por Orthomyxoviridae/prevenção & controle , Adenoviridae/genética , Administração Intranasal , Animais , Proteção Cruzada/imunologia , Feminino , Células HEK293 , Humanos , Vacinas contra Influenza/administração & dosagem , Vacinas contra Influenza/genética , Influenza Humana/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Infecções por Orthomyxoviridae/imunologia , Vacinação
20.
Radiat Prot Dosimetry ; 183(1-2): 213-218, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30576527

RESUMO

Cancer risk is an important limitation for galactic cosmic ray (GCR) exposures, which consist of a wide-energy range of protons, heavy ions and secondary radiation produced in shielding and tissues. Many studies suggest non-targeted effects (NTEs) occur for low doses of high-linear energy transfer (LET) radiation, leading to deviation from the linear dose response model used in radiation protection. We investigate corrections to quality factors (QF) for NTEs, which are used in predictions of fatal cancer risks for exploration missions. Prediction of fatal cancer risks for missions to the Martian moon, Phobos of 500-d and the Earth's moon of 365-d for average solar minimum condition show increases of 2- to 4-fold higher in the NTE model compared with the conventional model. Limitations in estimating uncertainties in NTE model parameters due to sparse radiobiology data at low doses are discussed.


Assuntos
Radiação Cósmica/efeitos adversos , Neoplasias Induzidas por Radiação/prevenção & controle , Proteção Radiológica/métodos , Voo Espacial , Astronautas , Humanos , Transferência Linear de Energia , Marte , Lua , Medição de Risco , Fatores de Risco
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